Laminated spring



April 5, 1932- H. SIEPRATH 1,852,132

LAMINATED SPRING v Filed Nov. 3, 1928 Figjj Fgz agr y di y y d? e Patented Apr. 5, 1932 HEINRICH sIErnA'rm-or AACHEN, GERMANY i LmvLINATEI)V sInING Application filed November 3, 1928, Serial No. 317,063, and in Germany July 21, 1927.

This invention relates to a suspension spring, particularly for railway vehlcles and it has for its object to provide means .for coupling the spring plates rigidly and 11nmovably to the spring buckle, so as to prevent displacement of said spring plates relatively to said buckle when the vehicle 1s 1n operation.

Numerous kinds of fastening means for the spring buckle are known but most of these have been frictional connections, that is to say, the spring buckle was fastened by means of keys or cotters or by pressing or shrinking it on to the plates. It is found in practice that such Xing means work loose in a short time under the influence of the lshocks which occur in working the vehicle. Fastening devices are also known in which rigid connection between the spring plates and the spring buckle is actually obtained but also at the expense of strength in the spring itself, or else itis necessary, when disassemblingv the connection to destroy some part orpparts. Thus, the strength of the spring has been ,r weakened when the spring plates were drilled through or furnished with lateral recesses, or undulating bends, or when the spring buckle was divided, slotted, drilled through or included curvilinear deflections. There are 1 again, methods of fastening which demand such a high degree of precision in the manufacture of the spring that, in addition to the drawback mentioned above, there is no prospect of making them on an economic i. basis.

Hence, the problem to be solved is the provision of a spring which satisfies the requirements of railway working and the manufacturing requirements also. The spring plates must not be weakenedin cross-section by drilling them through, recessing them or giving them undulating bends, the spring buckle must remain undivided and unweakened and all the parts of the spring and f its fastening must be capable of being produced inthe simplest form and as cheaply as possible and must also be interchangeable. In accordance with the invention it is also essential to obtain, in conjunction with the advantages aforesaid, a firm, immovable con'- E,

nection between the spring bucklezand the spring plates.`

All these requirements are fully met by the present invention. The construction of ythe spring and the manner in which it works can 'l be seen in the, accompanying drawings, in which; f

Fig. l is ka side elevation of the spring buckle and part of the spring.

Fig. -2 is a central sectionthrough the ET-1l I spring plates b having each in its upper face a longitudinal groove a and at its bottom face x a longitudinal rib engaging the groove of the plate below it, while said groove is engaged by the longitudinal rib of the plate above it.

rlhe central portion of each groove is 'considerably larger and deeper and forms a cavity or depression d, and just sothe central portion of each rib forms a downwardly directed boss d which engages the depression below it, while the depression-located just above and pertaining to the plate having that boss is engaged by the boss of the plate above it.

In building up the spring, the spring plates Y) are arranged in layers, one on top of another and interengaged by means of the bosses d and boss depressions CZ. rlhe lowest spring plate has its boss fitted into a corresponding boss depression in the bottom of the spring buckle 0. On Vthe uppermost spring plate lies the coupling plate e, the central boss d of which engages in the boss depression Z y of said plate while lateral lugs f on said couplingplate co-operate with the cheeks of the spring buckle c to keep said coupling place in position. The free space above the coupling plate is filled up with a liner plate g which holds the bundle of springs in engagement with the plate e. l

Assembly is effected by drawing the locking member, already inserted in the spring buckle, ,overl the packet of springs, previously bundled and bound together by clamping devices until the middle is reached. The

boss on the lowermost spring plate then springs into the boss depression of the spring buckle and the boss of the coupling plate into the boss rest on the uppermost spring plate.

In order to fill up ythe free space vbetween the coupling plate and the inner Yside ofthe spring buckle andto keep the bosses conadapted to receive the projection of the adjacent plates; a coupling plate contacting with one of the outermost plates of the set of plates and having at its four corners lateral lugs extending beyond` the adjacent plate; a liner plate contacting with said coupling plate, and a buckle encompassing al1 said members and having its lateral parts l0- cated between said lugs.

In testimony whereof I have hereunto set 75 my hand.

f HEINRICH SIEPRATI-I.

stantly in engagement the supplementary liner g is driven in. No separate fastening of the latter is necessary since it isnot subjected to any horizontal displacing forces.

The spring plates are now firmly connected to the buckle, since the main springk plate, to

which the horizontal forces are applied, whenv i the spring is working, is immovably coupled to the spring buckle by the boss d and the lugs f, while rall the other plates are inter-connected and connected to the lowerpart of the buckle by bosses and boss depressions.

' Lack of safety in the working of the vehicle,

in so far as the springs are concerned is thus, effectively overcome by the present invenv tion.

be applied as only the accidental dropping out of this plate need be secured. No strains whatever are exerted on the lining plate.

In the preferred form of the invention the fastening of said lining (packing) plate has been arranged in such away that the one end upper horizontal cheek of the spring buckle c, the other end of the lining (packing) plate being horizontally slotted and one end a ,bentv upwards. An accidental dropping of In order to secure the lining plate in the `spring buckle any kind of arrangement may -g is set off, and in consequence close to the bination,ra plurality'of superposed elastic plates having each on one of its faces a projection located in the center portion of the plate, and in its other'face a cavity'also locatedk inv the center portion of the plate and e 

